Dry cleaning composition

ABSTRACT

A DRY CLEANING COMPOSITION, HAVING A PH IN THE RANGE OF FROM ABOUT 6.5 TO ABOUT 9, CONSISTING ESSENTIALLY OF FROM ABOUT 20% TO ABOUT 99.94% BY WEIGHT OF A DRY CLEANING SOLVENT AND FROM ABOUT 0.06% TO ABOUT 80% OF AN ANIONIC DETERGENT COMPRISING THE MONOETHANOLAMINE SALT OF AN ESSENTIALLY PURE, BROAD CUT, LINEAR C8 TO C18 BENZENE SULFONIC ACID; THE COMPOSITION, WHEN EMPLOYED IN CONVENTIONAL DRY CLEANING OPERATIONS, IMPROVES FABRIC CLEANING AND REDUCES FABRIC GRAYING.

3,630,935 DRY CLEANING COMPOSITION Gordon W. Potter, In, Greenhills, Ohio, assignor to The Procter & Gamble Company, Cincinnati, Ohio No Drawing. Filed Dec. 16, 1969, Ser. No. 885,652 Int. Cl. (311d 11/18, 3/24; D061 1/04 US. Cl. 252-153 9 Claims ABSTRACT OF THE DISCLOSURE A dry cleaning composition, having a pH in the range of from about 6.5 to about 9, consisting essentially of from about 20% to about 99.94% by weight of a dry cleaning solvent and from about 0.06% to about 80% of an anionic detergent comprising the monoethanolamine salt of an essentially pure, broad cut, linear C to C benzene sulfonic acid; the composition, when employed in conventional dry cleaning operations, improves fabric cleaning and reduces fabric graying.

BACKGROUND OF THE INVENTION The invention herein generally relates to dry cleaning compositions and to the cleaning of fabrics therewith; more particularly, the invention herein pertains to dry cleaning compositions comprising a dry cleaning solvent and a specific anionic detergent, which compositions achieve improved insoluble and water-soluble soil removal and reduced fabric graying or soil redeposition.

It has long been considered good practice in the drycleaning industry to add small amounts of a fatty acid soap or an organic synthetic detergent to a dry cleaning solvent to effect efficient removal of water-soluble stains, such as those caused by various foods and the like. Detergents so employed include a variety of anionic, nonionic, and cationic compounds. Unfortunately, many such compounds exhibit relatively low levels of water-soluble stain removal and relatively high levels of fabric graying (i.e., soil redeposition) and often result in necessitating post-cleaning spot removal; other detergents impart relatively poor water-sol-ubilizing properties to the dry cleaning solvent, which can lead to the presence of excess water in the solvent-detergent system and, subsequently, to irreparable damage to water-sensitive garments, e.g., woolens; still other detergents require special additives or methods of incorporation into the solvent in order to pro vide and maintain a homogeneous emulsion or a singlephase necessary to permit use of the dry cleaning composition with the filtration apparatus conventionally used in retail and industrial dry cleaning operations. Thus, a detergent additive dry cleaning composition which avoids or substantially reduces the above-noted problems is highly desirable.

Past attempts to develop such a detergent additive dry cleaning composition have resulted in the general disclosure of alkanolamine salts. of higher alkylaryl sulfonic acid as suitable detergents; see, for example, U.S. Pats. 3,310,498; 3,310,499; and 3,254,029. However, the prior art has failed to teach or suggest the sole use of the specific detergent of the invention herein, which detergent characteristically embodies certain features (hereinafter disclosed) which are essential to the provision of dry cleaning compositions which achieve improved dry cleaning performance.

Accordingly, it is an object of the invention herein to provide a detergent additive dry cleaning composition which improves fabric cleaning and reduces fabric graymg.

Another object of the invention herein is to provide a finely dispersed, homogeneous dry cleaning composition comprising an anionic organic synthetic detergent and a United States Patent dry cleaning solvent, which composition achieves improved dry cleaning performance.

It is a further object of the invention herein to provide a single-phase dry cleaning composition which achieves improved insoluble and water-soluble stain removal and reduced fabric graying.

Still another object of the invention herein is to provide a single-phase dry cleaning composition comprising a dry cleaning solvent and an anionic organic synthetic detergent having certain features enabling the composition to achieve improved dry cleaning performance.

BRIEF SUMMARY OF THE INVENTION These and other objects are achieved by the invention herein which comprises a dry cleaning composition which preferably comprises (A) from about 20% to about 99.94% by Weight of a chlorinated dry cleaning solvent; and (B) from about 0.06% to about by weight of an anionic organic synthetic detergent which comprises the monoethanolamine salt of an essentially pure, broad cut, linear alkyl benzene sulfonic acid; wherein said alkyl is a mixture of alkyls having an average chain length of from about 8 to about 18 carbon atoms, and wherein said composition has a pH within the range of from about 6.5 to about 9.

DETAILED DESCRIPTION OF THE INVENTION In a conventional process of dry cleaning fabrics, the soiled fabrics are agitated in a volatile organic dry cleaning solvent which is relatively immiscible with water. Such solvents are generally effective for the removal of grease and oil stains as well as dust, dirt, lint and the like which commonly adhere to the fabrics and to the grease and oil thereon. The agitation is generally accomplished by inserting the fabrics into a perforated cylinder which is rotated in the solvent bath. The solvent is usually circulated by means of a pump through a filter which removes suspended soil particles; by means of recycling and filtering, the solvent can generally be reused many times and, after becoming badly contaminated, can be distilled and used again. After suflicient treatment, the fabrics are usually subjected to centrifugal action to remove excess solvent and then placed in a rotating cylinder or drying cabinet wherein final traces of solvent are removed by a current of warm air.

To promote the removal of water-soluble soil, such as those caused by various foods and the like, from the fabrics, the solvent generally incorporates small amounts of water and/or a detergent. Many detergents, besides having detersive qualities, also have absorbefacient characteristics which permit water (either added to the system or resulting from the moisture in the fabrics or the relative humidity of the dry cleaning system) to become finely disperscd throughout the solvent and to achieve better watersoluble soil removal from the fabrics.

It has now been unexpectedly found that when the solvent consists essentially of a chlorinated dry cleaning solvent and the detergent comprises the monoethanolamine salt of a linear alkyl (from about C to about C benzene sulfonic acid, wherein the alkyl is a broad cut having a distribution of carbon chain lengths and wherein the alkyl benzene sulfonic acid is essentially pure, the resulting dry cleaning composition achieves improved fabric cleaning (i.e., insoluble and water-soluble soil removal) and reduced fabric graying. Advantageously, the use of a composition herein can result in a significant reduction in the labor and time currently often expended to remove spots and stains which remain after general fabric treatment, e.g., by the abovedescribed dry cleaning process.

The compositions herein are advantageously marketed as a concentrate of the detergent and can, therefore, em-

ploy detergent concentrations up to about 80% by weight of the composition, the balance being, preferably a chlorinated, dry cleaning solvent; for direct use, the compositions herein can also be marketed as or the concentrate diluted (e.g., wit-h perchlorethylene) to a dry cleaning composition having a detergent concentration of from about 0.06% to about 5% by Weight of the composition. The compositions herein have a pH within the range of from about 6.5 to about 9; the pI-Is reported herein and in the appended claims are based on the pH of the composition having a 0.6% by weight detergent concentration at a relative humidity of about 75%.

According to the invention herein, there are provided dry cleaning compositions which improve fabric cleaning and reduce fabric graying, said compositions, preferably, consisting essentially of:

(A) from about 20% to about 99.94% by weight of a chlorinated dry cleaning solvent; and

(B) from about 0.06% to about 80% by weight of an anionic organic synthetic detergent which comprises the monoethanolamine salt of an essentially pure, broad cut, linear alkyl benzene sulfonic acid;

wherein said alkyl is a mixture of alkyls having an average chain length of from about 8 to about 18 carbon atoms, and wherein said composition has a pH within the range of from about 6.5 to about 9.

Essential to the invention herein is the use of an essentially pure, linear alkyl benzene sulfonic acid, wherein the alkyl, as termed herein and in the appended claims, is a mixture of alkyls as described above. For best results, the alkyls herein, preferably, have at least about 4 different carbon chain lengths, each of which contains from about 6 to about 20 carbon atoms, wherein at least about 80% by weight of the chain lengths are within the range of from about 8 to about 18 carbon atoms and wherein at least two of the chain lengths comprise at least about 20% by weight of the alkyl. In the trade, such mixed alkyls are often termed broad cuts; thuS, for example, a broad cut C or dodecyl benzene sulfonic acid has a mixture of alkyls having an average chain length of about 12 (specifically between 11 and 12) carbon atoms, specifically, consisting essentially of (percent is by weight) C from 0% to about 0.4%

C from about 17.7% to about 19.99% C from about 40.6% to about 42.8% C from about 29.4% to about 32.7% C from about 6.6% to about 9.1% C from about 0.2% to about 0.23%

Similarly, a broad cut C (octyl) or C (octadecyl) benzene sulfonic acid has a mixture of alkyls having an average chain length of about 8 and 18 carbon atoms, respectively.

It has now been unexpectedly found that when the monoethanolamine salt of an alkyl benzene sulfonic acid comprising a mixture of linear alkyl carbon chain lengths (i.e., a broad cut, linear alkyl benzene sulfonic acid) is employed as a detergent in a dry cleaning solvent, fabrics treated with the composition generally exhibit an improved level of cleaning and a reduced level of graying in comparison with, e.g., a pure cut, linear, alkyl benzene sulfonic acid (i.e., one in which the alkyl does not contain a mixture or distribution of various carbon chain lengths, but, instead, has only one alkyl having a definite and fixed carbon chain length).

Suitable broad cut, linear alkyls for use in the MEA- LAS compounds of the invention herein include those wherein the chain lengths average from about 8 to about 18 carbon atoms; specific examples of such compounds include, e.g., monoethanolamine salts of broad cut, linear octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, he-ptadecyl, and octadecyl benzene sulfonic acid wherein the chain lengths average about C 4 9 10 11 12 13 14 15, 10 17 and C18 carbon atoms, respectively.

Methods which can be utilized to prepare the detergents employed in the dry cleaning compositions herein are generally known in the art. For example, a suitable method comprises, firstly, reacting a linear, parafiinic hydrocarbon (e.g., a petroleum distillate) containing a mixture of alkyls having a desired average carbon chain length within the range of from about 8 to about 18 with chlorine under conventional methods to obtain the chlorinated broad cut, linear hydrocarbon which is thereafter reacted with benzene (e.g., under Friedel-Crafts reaction conditions) to obtain the broad cut, linear alkyl benzene; the latter compound can alternatively be prepared by reacting the linear, paraffinic hydrocarbon with benzene with, e.g., hydrofluoric acid. The broad cut, linear, alkyl benzene is thereafter sulfonated, preferably, with sulfur trioxide to form the broad cut, linear alkyl benzene sulfonic acid which is thereafter neutralized, e.g., by mixing equimolar amounts of monoethanolamine and the alkyl benzene sulfonic acid to form a monethanolamine alkyl benzene sulfonate employed as a detergent herein.

It is further essential to the invention herein that the broad cut, linear alkyl benzene sulfonic acid (or its monethanolamine salt) be essentially pure. Surprisingly, it has also been found that by-products, which can result when certain methods are used to sulfonate an alkyl benzene (broad or pure cut) generally inhibit fabric cleaning and/or promote undesirable fabric graying despite the fact that such by-products, especially those occurring after the neutralization step, may themselves be otherwise suitable detergents.

By way of brief explanation, one commonly used sulfonation method comprises reacting an alkyl benzene with chlorosulfonic acid in accordance with the following unbalanced reaction:

Unless the resulting alkyl benzene sulfonic acid is purified of the large amount of other reaction by-products, subsequent neutralization of the reaction products will yield the desired MEA-LAS detergent and other neutralization by-products which generally inhibit dry cleaning performance of the compositions herein. Thus, for example, when the products of Reaction I are neutralized with monoethanolamine (MBA), in accordance with Reaction 2, the reaction products include an MEA-LAS detergent and an MBA alkyl benzene sulfonamide plus other MEA salt by-products; unless removed, the presence of the sulfonamide (itself an often used detergent) in the compositions herein generally inhibits their dry cleaning performance.

I lts OgNIIZCllZOLlZOH RSO Cl (MEA-LA S) IIZNCiIZOHZOIE (MEA) R-so,Nnoinon,oir

(MEA alkyl benzene sulionaruide) MEA salt lay-products [lb-broad cut (2 0 alkyl] The presence of such by-products is generally avoided when, e.g., the above-described preferred sulfonation procedures are used; alternatively, such by-products, when formed, e.g., from the use of reaction (1) above as a method of sulfonation, can conveniently be removed after their formation by techniques known in the art, e.g., by

the use of ion exchange resins. It is not desirable, for economical and practical reasons, to neutralize the alkyl benzene sulfonic acid in the presence of such by-products as are formed in Reaction 1 above; however, if desired, neutralization can be so accomplished and the resulting by-products (e.g. the sulfonamide in Reaction 2 above) can thereafter be removed by conventional techniques, e.g., by the use of ion exchange resins prior to formulating the MEA-LAS into a composition herein.

Also essential to the invention herein is the use of the monoethanolamine salt of the alkyl benzene sulfonic acid. Surprisingly, only the monoethanolamine (MEA) salt of the linear alkyl benzene sulfonic acid provides a detergent herein which, when incorporated into the chlorinated solvents (preferred herein), achieves a desirable singlephase dry cleaning composition; other alkanolamine salts (e.g., dimethanolamine, diethanolamine, triisopropanolamine, and the like) of the alkyL benzene sulfonic acids employed herein provide detergents which generally are either less effective in performance or undesirably result in unfilterable two-phase dry cleaning compositions.

It has been found, however, that other alkanolamines can be employed in admixture with MEA to form salts of the broad cut, linear, alkyl benzene sulfonic acids used herein, which detergents, when utilized as substitutes for MEA-LAS, achieve elfective single-phase dry cleaning compositions. Examples of such other alkanolamines which are suitable for use in admixtures with MBA, include, e.g., the mono-, di-, and tri-alkanolamines wherein the alkanol is methanol, propanol, isopropanol, and butanol, and diand tri-alkanolamines wherein the alkanol is ethanol, and mixtures thereof. Specific examples of such compounds are as follows:

monomethanolamine; dimethanolamine; trimethanolamine; monopropanolamine dipropanolamine; tripropanolamine; monoisopropanolamine; diisopropanolamine; triisopropanolamine; monobutanolamine; dibutanolamine; and, tributanolamine.

Specific examples of preferred alkanolamines for use in admixtures with MEA include diethanolamine (DEA), triethanolamine (TEA), and monoisopropanolamine (IPA).

Any one or more of the foregoing other alkanolamines can be employed in admixture with MEA. When any of such other alkanolamines are employed in admixture with MEA, the amounts in which they can be admixed will vary depending upon the specific other alkanolamine or alkanolamines being used. Generally, the amount of MEA used in the admixture should be sufficient to provide filterable dry cleaning compositions which should be finely dispersed, homogeneous or, preferably, single-phase compositions; for example, an admixture of MEA with up to about 90% by weight IPA, with up to about 80% by weight DEA, or with up to about 40% by weight TEA provides detergent additive dry cleaning compositions which are single-phase.

Accordingly, the detergent additive of the compositions herein can further comprise an alkanolamine salt of an essentially pure, broad cut, linear alkyl benzene sulfonic acid employed herein, wherein the alkanolamine consists essentially of an admixture of from about to about 99% by weight monoethanolamine and from about 1% to about 90% by weight of one or more other alkanolamines selected from the group consisting of (A) mono-, di-, and tri-alkanolamines wherein the alkanol is methanol, propanol, isopropanol, and butanol, (B) diand tri-alkanolamines wherein the alkanol is ethanol, and (C) mixtures thereof.

The dry cleaning compositions herein comprise a dry cleaning solvent, many of which are well known in the art. Preferred solvents are chlorinated solvents, such as perchlorethylene, trichloroethylene, carbon tetrachloride, and methyl chloroform; particularly preferred solvents are perchlorethylene and methyl chloroform, especially perchlorethylene.

The selection of a dry cleaning solvent for use herein importantly depends upon whether the resulting dry cleaning composition will be sold at use levels, i.e., ready for direct incorporation and use in dry cleaning operations, or at concentrated levels, i.e., concentrated compositions (up to about 80% by weight concentrations of the detergent) which require dilution with additional dry cleaning solvent prior to incorporation and use.

In the former case, it is essential that the composition be either a finely dispersed, homogeneous emulsion or, preferably, a single phase and comprise a substantial amount of a chlorinated solvent selected from the abovedisclosed group, preferably perchlorethylene; other conventional dry-cleaning solvents, generally categorized as hydrocarbons, such as Stoddards solvent, naphtha, 140 solvent, kerosene, gasoline, mineral spirits, mineral oil, and aromatic hydrocarbons, (e.g., benzene, toluene, xylene, or mixtures thereof) are not suitable for use with the detergent additive of the use level compositions herein as a major component thereof and, when so used, generally result in compositions which undesirably are not filterable and/or are not satisfactory in dry cleaning performance.

Less concern need be given to providing a single-phase dry cleaning composition to be sold at concentrated levels. in this case, the dry cleaning solvent employed can be selected from the chlorinated solvents or from the hydrocarbon (preferably, an aromatic hydrocarbon) solvents disclosed above, as well as mixtures thereof. It will be understood, however, that such concentrated compositions should be diluted with a chlorinated dry cleaning solvent to obtain a use level composition which is filterable. When the concentrated compositions employ a hydrocarbon solvent, the solvent of the use level compositions derived therefrom will be an admixture of the chlorinated solvent and the hydrocarbon solvent. Because the required dilution necessitates the addition of large amounts of the chlorinated solvent, the resulting use level composition generally contains only a low amount (up to about 20% by weight of the composition) of the hydrocarbon solvent and, further, is generally in the form of a filterable finely dispersed, homogeneous emulsion which, to the naked eye, generally appears as a single phase. For example, by adding a sutficient amount of a suitable chlorinated solvent to a concentrated composition herein which consists essentially of about 20% by weight MEA-LAS (C and about 80% by weight hydrocarbon solvent, e.g., a mixture of benzene, toluene, and xylene, a use level composition can be achieved which consists essentially of about 5% by weight MEA- LAS (C and about 95% by weight solvent, wherein the solvent is an admixture of the chlorinated solvent and the hydrocarbon solvent, specifically about by weight (of the composition) chlorinated solvent and about 21% by weight of the total solvent; diluting concentrated compositions to smaller detergent concentrations provide use level compositions having smaller amounts of the hydrocarbon solvent. Preferably, the solvent employed in the concentrated compositions herein is a chlorinated solvent, especially perchlorethylene, in which event the compositions, after dilution, are filterable as well as single phase.

The amount of detergent which can be employed in the compositions herein generally ranges from about 0.06% to about by weight of the composition; correspondingly, the amount of solvent utilized can range from about 20% to about 99.94% by weight of the composition. The above ranges cover both the use level and concentrate level compositions of the invention herein.

With regard to concentrated compositions herein, the amount of detergent can generally range from about 20% to about 80%, preferably about 40%, and the solvent can generally range from about 20% to about 80%, preferably about 60%, by weight of the composition.

With regard to the use level compositions herein, the amount of detergent can generally range from about 0.06% to about preferably about 0.3%, and the solvent can generally range from about 95% to about 99.94%, preferably about 99.7%, by weight of the composition. When a concentrated level composition herein, comprising a hydrocarbon solvent, is diluted with, e.g., perchlorethylene to obtain a use level composition, the solvent of the resulting composition contains an amount (up to about by weight of the composition) of the hydrocarbon solvent.

Generally, the compositions herein can have a pH (determined at 0.6% by weight concentration of detergent and a 75% solvent relative humidity) of from about 6.5 to about 9, preferably from about 7 to about 8. Below a pH of about 6.5, the compositions tend to be too acidic and can cause corrosion and other undesirable effects; above a pH of about 9, the compositions can have an undesirable effect on fabric dyes, especially acid-set dyes.

A particularly preferred use level composition of the invention herein consists essentially of about 0.3% by weight MEA-LAS (C and about 99.7% by weight perchlorethylene, wherein the composition has a pH of about 7. This composition exhibits a highly desirable single-phase characteristic and generally achieves high levels of fabric cleaning with reduced levels of fabric graying.

Optionally, the compositions herein can additionally contain one or more of a variety of other fabric treating agents which are soluble in the dry cleaning solvent. Examples of such agents which are especially desirable for inclusion herein are, e.g., brighteners (which can be nonionic or cationic and, preferably, are of the anionic stilbene-derivative types), perfumes, antistatic agents, fabric softening agents, and germicides. Generally, the amounts of such agents (e.g., brighteners and perfumes) employed herein are quite small and range from about 0.01% to about 3% by weight of a concentrated level composition herein and from about 0.0001% to about 0.03% by weight of a use level composition herein; however, larger amounts can, if desired, be used.

The following examples will serve to further illustrate the invention herein and it will be understood that said examples in no way limit the invention.

The examples herein generally illustrate, by way of comparison, the improved dry cleaning performance achieved by or the essential features of the compositions herein.

Unless otherwise noted, the comparison tests performed therein, briefly, involved the following procedure:

Test swatches (4" x 4") are cut from bleached, mercerized cotton print cloth. For each test, 18 swatches are used; nine are clean or unsoiled swatches and nine are each soiled with an insoluble soil commonly referred to as rug-beater soil. Four readings of each swatch, clean and soiled, are then taken on a reflectometer to obtain its original reflectance (R using an 81.4 percent reflectance backplate (filter G) with the swatches being read in nine layers (i.e., swatches are backed by suflicient fabric, which is washed in the reference composition, to make nine layers). The swatches are thereafter placed into a relative humidity (R.H.) conditioner and conditioned for at least 36 hours over a saturated sodium acetate solution at 75% RH. and about 75 F. Three clean and three soiled swatches are then placed into each of three 500 ml. Laundcr-Ometer cans along with stainlesssteel balls and 150 ml. of a dry cleaning composition having a measured weight concentration of detergent as measured at R.H. by conventional techniques. Each can, with its contents, is then placed into the Launder-Ometer and run for one hour, after which each can is removed, the swatches drained and separated by pouring the contents through a funnel, and the swatches dipped about 10 times in clean perchlorethylene. The swatches are thereafter placed on a blotter and allowed to dry, after which each swatch is again similarly read on the reflectometer to obtain its final reflectance (R Cleaning performance is calculated using the average original and final reflectances for the nine soiled swatches in accordance with the equation:

f R0 (reference composition) Graying (G) is calculated using the average original and final reflectances for the nine clean swatches in accordance with Equation 3 above. Overall dry cleaning performance is then determined by dividing the cleaning performance (C) by the graying performance (G) to obtain the 'C/ G ratio.

The reference composition referred to above and employed in the examples for comparative purposes, is one generally used as a standard in the industry and is a dry cleaning composition consisting essentially of about 99.4% by weight perchlorethylene as the solvent and about 0.6% of a detergent consisting essentially of sodium di-noctyl sulfosuccinate. This composition makes an excellent standard because the detergent is a relatively pure chemical compound available in pure grade; the composition has been assigned a C value of l, a G value of 1 and a C/G ratio of 1.

Unless otherwise noted in the examples, all percentages and parts are by weight. Generally, a difference of 10% or better between C/ G ratios is considered significant, in accordance with recognized grading practice in the industry. Variations in C/ G ratios of any single composition repeatedly appearing in the following examples is generally due to the varying soil loads of the test swatches and/or to experimental error. Generally, higher C/ G ratios reflect both better fabric cleaning and lower fabric graying.

EXAMPLE I Utilizing the testing procedures described in the foregoing discussion, two separate tests were run for each of the following dry cleaning compositions; compositions B, C, and D were commercially available dry cleaning compositions (concentrates) which were diluted with perchlorethylene to their recommended use level concentrations.

Composition B Composition A: Reference Composition Percent .9%--Admixture comprising:

(a) Potassium salt of a linear C C alkyl benzene sulfonic acid 40 (b) Nonionic ethoxylate of a C -C alkyl benzene 40 (c) Hydrocarbon solvent 20 99. l %Perchlorethylene Composition .C

Percent 0.6%-Admixture comprising:

(a) C -C amine salt of a linear C alkyl benzene sulfonic acid 50 (b) Nonionic ethoxylate of a C -C alkyl benzene 40 (c) Hydrocarbon solvent 10 99.4 Perchlorethylene Composition D Percent 0.9%-Admixture comprising:

(a) C -C amine salt of a linear C alkyl benzene 20 (b) Nonionic ethoxylate of a C -C alkyl benzene and magnesium phosphate esters thereof 40 (c) Hydrocarbon solvent 40 99. l Perchlorethylene Composition E A composition consisting essentially of:

0.3 %Isopropylamine salt of an essentially pure, broad cut, linear C alkyl benzene sulfonic acid 99.7%Perchlorethylene Composition F A composition of the invention herein having a pH of about 7 and consisting essentially of:

O.3%-MEA salt of an essentially pure, broad cut, linear C (dodecyl) benzene sulfonic acid 99.7 %-Perchlorethylene The C, G and C/G ratio values were computed for each of the three cans of each composition employed in each of the two tests; the C/ G ratios were averaged for each test and are reported below.

Composition C D E O/G ratio First test Second test. i. Average The results reflect the improved dry cleaning performance (i.e., improved fabric cleaning and reduced fabric graying) achieved by utilization of the compositions of the invention herein.

EXAMPLE II For purposes of comparison to further illustrate the invention herein, the procedure employed in Example I was repeated to, specifically, point up the inhibited dry cleaning performance obtained when the detergent additives or the compositions herein themselves contain impurities.

Specifically, MEA broad cut, linear C alkyl benzene sulfonamide was prepared by conventional methods and incorporated into dry cleaning compositions (G, H and I) of the following description:

0.3 %Admixture of:

(a) MEA-LAS (C (b) sulfonamide 99.7 %-Perchlorethylene wherein various Weight ratios of the MEA-LAS (C to the sulfonamide were employed. These compositions were tested and their results compared, relative to the Reference Composition, to those of Composition F (see Example I) and of Composition I which consisted essentially of 0.3% sulfonamide and 99.7% Perchlorethylene.

The results are as follows:

Composition F G H I 3' Weight ratio: MEA-LAS (On) to sulfonamide 14:1 13:2 4:1 C/G ratio 3.68 3.33 2.85 2. 47 1.3

The results illustrate the improved dry cleaning performance obtained by employing the MEA salt of an essentially pure, broad cut, linear alkyl benzene sulfonic acid and, further, reflect the inhibited performance obtained when impurities are present in the compositions herein.

10 EXAMPLE III To further illustrate the necessity of employing an essentially pure detergent additive to achieve improved dry cleaning performance, the procedure of Example I was repeated to compare Composition F therein with compositions, characteristic of many commercially available dry cleaning compositions, described as follows:

Composition K 0.3%-MEALAS (C 0.12%Condensation reaction product of 5 moles of ethylene oxide with one mole of nonyl phenol 99.5 8 -Perchlorethylene Composition L 0.3 %MEA-LAS (C 0.12%-Condensation reaction product of 4 moles of ethylene oxide with one mole of nonyl phenol 99.58%Perchlorethylene The C/G ratios for the compositions were then calculated and the results, relative to the Reference Composition, are as follows:

Composition: C/ G ratio F 3.10 K 2.20 L 2.60

These results illustrate the generally improved dry cleaning performance achieved with the compositions herein in comparison with compositions additionally ernploying other detergent additives.

EXAMPLE IV The procedure employed in Example I was repeated to further illustrate the improved dry cleaning performance achieved by employing a broad cut, essentially pure, linear alkyl benzene sulfonic acid.

In this example, Composition F of the invention herein was compared to a composition (Composition M) consisting essentially of about 0.3% of the MEA salt of pure cut, linear C alkyl benzene sulfonic acid. The C/ G ratios were calculated, and the results, relative to the Reference Composition, are as follows:

Composition: C/ G ratio F 4.22 M 2.78

The results clearly indicate that employing a broad cut alkyl in the detergent additive achieves dry cleaning compositions which exhibit improved performances in comparison to compositions containing a detergent additive having a pure cut alkyl.

EXAMPLE V The compositions of the invention herein are advantageously suitable for the desirable incorporation of optional additives. Suitable dry cleaning compositions (pH about 7) of the invention herein, which compositions contain a perfume and a brightener, consist essentially of about:

(a) Use level composition: Percent MEA-LAS (C 0.3 Perchlorethylene 99.6978 Perfume 0.002 Anionic brightener 0.0002

(b) Concentrated level composition:

MEA-LAS (C 40.00 Perchlorethylene 59.73 Perfume 0.25 Anionic brightener 0.02

1 1 EXAMPLE VI A concentrated dry cleaning composition was made and consisted essentially of about 60% by weight perchlorethylene and about 40% by weight of an anionic synthetic organic detergent which was the monoethanolamine salt of an essentially pure, broad cut linear alkyl benzene sulfonic acid wherein the alkyl was a mixture of alkyls having an average chain length of about 12 carbon atoms (i.e., broad cut dodecyl).

The concentrated composition was diluted with sufficient additional amounts of perchlorethylene to achieve a use level composition similar to Composition F having a pH of about 7 and consisting essentially of about 0.3% of the anionic detergent and about 99.7% perchlorethylene. Thereafter, the diluted or use level composition was tested and compared in accordance with the procedures described in Example I and the results were similar to those reported therein.

EXAMPLE VII When the procedure of Example VI is repeated substituting a hydrocarbon mixture of benzene, toluene, and xylene for the perchlorethylene employed as a solvent in the concentrated composition described therein, the resulting composition (pH about 8), after being diluted with perchlorethylene, exhibits the characteristics of a very finely dispersed, homogeneous emulsion in which the solvent is an admixture of about 99.25% perchlorethylene and about 0.45% of the hydrocarbon mixture (percent is by weight of the composition). When employed in conventional dry cleaning operations, the composition is filterable and achieves dry cleaning performance results similar to those reported in Example VI.

When, in any of the foregoing examples, the MEA salt of an essentially pure, broad cut, linear octyl, nonyl, decyl, undecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, or octadecyl benzene sulfonic acid is substituted for the C MEA-LAS employed therein, results similar to those therein are obtained.

Similarly, when in any of the foregoing examples, the MEA employed in the C MEA-LAS therein is substituted with an admixture of alkanolamines consisting of about 20% by weight MEA and about 80% by weight DEA or consisting of about 60% by weight MBA and about 40% by weight TEA, results similar to those reported therein are obtained.

Similarly, when in any of the foregoing examples, the perchlorethylene employed therein is substituted with methyl chloroform, results similar to those obtained therein are achieved.

Having described the invention in detail, what is now claimed is:

1. A dry cleaning composition with improved dry cleaning performance, said composition consisting essentially of:

(A) from about 20% to about 99.94% by weight of a chlorinated dry cleaning solvent; and

(B) from about 0.06% to about 80% by weight of an anionic organic synthetic detergent which consists essentially of an essentially pure, broad cut, linear alkyl benzene sulfonic acid which has been neutralized with monoethanolamine, and which is substantially free of monoethanolamine alkyl benzene sulfonamide and monoethanolamine salt by-products, and wherein said alkyl in said alkyl benzene sulfonic acid is a mixture of alkyls having an average chain length of from about 8 to about 18 carbon atoms,

12 and wherein said composition has a pH within the range of about 6.5 to about 9.

2. A dry cleaning composition in accordance with claim 1, wherein said chlorinated dry cleaning solvent is selected from the group consisting of perchlorethylene, trichlorethylene, carbon tetrachloride, and methyl chloroform.

3. A dry cleaning composition in accordance with claim 2, wherein said solvent is selected from the group consisting of perchlorethylene and methyl chloroform.

4. A dry cleaning composition in accordance with claim 3, wherein said composition consists essentially of about 60% by weight perchlorethylene, and about 40% by weight of the monoethanolamine salt of an essentially pure, broad cut, linear alkyl benzene sulfonic acid, wherein said alkyl is a mixture of alkyls having an average chain length of between 11 and 12 carbon atoms.

5. A dry cleaning composition in accordance with claim 3, wherein said composition is single phase and consists essentially of from about 0.06% by weight to about 5% by weight of said detergent and from about 95% to about 99.94% by weight of said solvent.

6. A dry cleaning composition in accordance with claim 5, wherein said composition consists essentially of about 99.7% by weight perchlorethylene and about 0.3% by weight of the monoethanolamine salt of an essentially pure, broad cut linear alkyl benzene sulfonic acid, wherein said alkyl is a mixture of alkyls having an average chain length of between 11 and 12 carbon atoms and wherein said composition has a pH of about 7.

7. A dry cleaning composition in accordance with claim 5, wherein said alkyl is a mixture of alkyls having an average chain length of about 12 carbon atoms.

8. A dry cleaning composition in accordance with claim 7 wherein said pH is about 7.

9. A concentrated dry cleaning composition with improved dry cleaning performance, said composition consisting essentially of:

(A) from about 20% to about by weight of a chlorinated dry cleaning solvent; and

(B) from about 20% to about 80% by weight of an anionic organic synthetic detergent which consists essentially of an essentially pure, broad cut, linear alkyl benzene sulfonic acid which has been neutralized with monoethanolamine, and which is substantially free of monoethanolamine alkyl benzene sulfonamide and monoethanolamine salt by-products, and wherein said alkyl in said alkyl benzene sulfonic acid is a mixture of alkyls having an average chain length of from about 8 to about 18 carbon atoms and wherein said composition has a pH within the range of about 6.5 to about 9.

References Cited UNITED STATES PATENTS LEON D. ROSDOL, Primary Examiner H. A. PITLICK, Assistant Examiner U.S. Cl. X.R.

255 2 3 V UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION -Inventor(s) Gordon W. Potter, Jr.

R is certified that error appears in the above-identified patent. and that said Letters Patent are hereby corrected as shown below:

Column 8, line 55 delete "Composition B" and insert therefor Composition A: Reference Composition Column 8, line 57, delete "Composition A: Reference Composition" and insert therefor Composition B Column 9, line 32, delete "4.38" and insert therefor 4.36

Signed and sealed this L th day of July 1972.

(SEAL) Attestz' EDWARD PLFLETGHEH, JR. ROBERT GOTTSCHALK Attestlng Officer Commissioner of Patents 

